User Manual

Data Security in GoodReader

GoodReader is very serious about data security. In fact, it`s hard to find another mobile app that offers so many security-related features for your files. The features work in different layers and apply to different aspects of making your data secure. There`s so much that we offer, it sometimes becomes confusing. But fear not! Here, we will give you a general introduction to Data Security in GoodReader.


There are a few things you can do to ensure the security of your files:


For Storing Files Inside GoodReader


The following features are application-level. Meaning that they do not affect the contents of your files but rather the way GoodReader is storing and handling the file objects. For example, the GoodReader`s file encryption doesn`t work — or even make sense — outside the app, only inside the GoodReader`s file storage container. If you need to send a file somewhere, it will be decrypted prior to leaving GoodReader, and exported in its original unencrypted plain-text form.


  • Password-protecting the app. Here`s how to do it. Now simply password-protecting the app isn`t that much of a protection. Unless you choose to enable our Military-Grade File Encryption, the files themselves are still going to be an easy target. However, there`s more inside GoodReader than just files. For instance, there could be remote server connections that could be used to steal your data from remote servers by anyone who has access to GoodReader app on your device. Making sure GoodReader won`t launch without a password is a good way to secure your remote data.


  • Password-protecting individual files and folders. The name says it all — you can`t open a file or a folder unless you enter a password. Here`s how it works. Please note that this feature only makes sense if you enabled our Military-Grade File Encryption. Otherwise the password for files is pretty much useless since Apple allowed its standard pre-installed app Files to browse inside other apps` file containers. But with Encryption enabled, Files app or no Files app, your data will be secure.


  • Military-Grade File Encryption. This feature is a crown jewel of our Data Security features collection. It works in conjunction with the two previous features — the app or file passwords. However you choose to password-protect your data — either by setting a password on the entire app, or on individual files — GoodReader will encrypt the protected data. After that, even if someone somehow manages to extract the file from your device by cracking the device`s Passcode, without knowing the GoodReader`s internal password, which is different from your device`s Passcode, the file will be an unreadable digital garbage.
    When you`re opening encrypted files, GoodReader will work tirelessly behind the scenes to feed the decrypted data to the viewing engine on-the-fly, making sure that no decrypted data is ever written on disk. And in cases when it has to happen — like when you have to email a file — GoodReader will warn you about exposing your sensitive data, and offer one of the solutions — see below.


For Sending Files Away


So you`ve secured your files inside GoodReader. Great. But what about exporting them? Like sending in an email? Or uploading to a server for collaboration with coworkers? Once the file leaves GoodReader, the application-level measures won`t work any more. You need file-level ones. As in "actually modifying the contents of files to make them protected." No worries, we`ve got your back:


  • Sending PDF files away. No doubt, you`ve come across some PDF files that won`t open unless you enter a password. This is an option built into the official PDF Standard. And, because it`s a file-level feature, it travels along with the file. It looks like a regular file, but everythinbg inside it is encrypted. And since it`s in the PDF Standard, every PDF reader on every platform knows how to open these encrypted PDFs. So every time you have to export a PDF file from GoodReader, the app will offer you an option to add a PDF password protection to it. Use this feature whenever you need to send a sensitive PDF file away, especially in an email! (See the note below.)
    But it gets even better! Before the AES-256 — a very strong encryption — became popular, the PDF Standard used to use simpler and less secure encryption techniques. Those old techniques are so weak, you can even find an online tool to crack those PDF passwords in seconds, for free! But no such luck cracking latest-to-date AES-256 encryption. So if you open an old, easy-to-crack PDF file with a weak encryption in GoodReader, the app will warn you and offer to upgrade the encryption to AES-256.


  • Sending any files — and folders — away in ZIP archives. Ok. So you`ve added passwords to all your sensitive PDFs to send out. But what about other file types? No worries. Just compress them into a password-protected encrypted ZIP archive. Just like with PDFs, encryption inside a ZIP file is a standard ZIP feature. It will travel with the file, and every unzipper on every platform will know how to open it provided a correct password.
    Also, encrypted or not, sending ZIP archives is the only way to email entire folders, even with complex subfolder structures. So you might find the feature of creating ZIP archives extremely useful, even if you don`t add passwords to them.


Fun (but also scary) fact
Not a lot of people realize that the email protocol we still use nowadays was invented more than 40 years ago. It didn`t even occur to the inventors at the time that some people will be actively hunting for sensitive and personal information all over the Web, trying to intercept and abuse everything there is to intercept and abuse. Oh those happy days! ;-) As a result, to this very day, every time you send an email with a file attachment, the file travels through any number of random servers anywhere in the world, in an absolutely open plain-text form! Think about it the next time you`re sending your confidential financial records to your lawyer in an email.



Other Tools


Some lesser-known security-related features, specific to PDF files only, that may prove to be a powerful addition to your toolbox:


  • Flattening PDF files. PDF Annotations, including simple handwritten signatures on documents, are meant to be freely editable — and deletable — objects on top of a non-editable PDF page, by design. And as far as annotations go, it`s a good design. However, sometimes you may want to imprint those editable drawings into the original page contents, making them permanent so no one could accidentally delete or misplace them any more. We call this process "Flattening" — placing the annotations into the original PDF page contents, making them regular non-editable PDF drawings that stay at their designated places on the page no matter what. This is how to do it. Also, there is such thing as Unflattening — reverting previously flattened annotations to their original editable state. Please note that you may — and probably should — choose to disallow futher unflattening at the time of flattening a file in the PDF Settings in GoodReader.


  • Secure Photocopy. Recently, there`s been a few high-profile legal cases where lawyers submitted PDF files to courts, carefully redacting sensitive information, only to have journalists take those PDFs from the court`s archives and copy-paste the "redacted" text from underneath the black rectangles drawn on top of PDF pages. Well, as someone who has deep knowledge of the PDF file format, we`re not suprised at all this kind of thing is happening every once in a while. But guess what — GoodReader has got you covered! Introducing a feature we call Secure Photocopy. Imagine that you put a black tape over a sensitive text and give that paper to someone. Nothing stops that person from removing the tape and reading what you so carefully tried to conceal. This is exactly what happened in those high-profile cases. Now imagine that before handing the paper out, you make a photocopy of it. And give it away instead of the original. There`s no more black tape to remove, no hidden-but-still-present text to uncover. This is what we can do for you. Produce a sort of a "photocopy" where there will be no hidden text, no deleted-but-still-present pages, etc. This will be a 100% what-you-see-is-what-you-get file.



Related Questions

Excellent iOS document multi tool.

UPDATE: Working great in iOS 11, including popover and split screen.

If you use your iPad for any serious reading or reviewing of documents, buy GoodReader immediately. It`s power in managing documents will allow you to get to pretty much any storage service, and the powerful markup tools will make a quick job of reviewing and editing.

My power tip: once you`ve reviewed a document, GoodReader can send both the marked-up document *and* a summary of your markup via email in one click. Makes document review a breeze.

Technodad, Review on the App Store

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